Tag Archives: function

Bash function for making locate find exact matches

This is one of the coolest and most useful things to add to my UNIX/Linux profile that I have come across in a long time. I use the locate command a lot (slocate naturally) as I am sure all of us command line monkeys do. How many times have you been frustrated by the billions of lines of results flying by your screen, piping through more or less, trying to find the one nugget of goodness that you really need? Especially when you actually know the correct name of it, just not where it lives? This is where this comes in handy (this is where this? man I am eloquent)! Add this function to your bash profile (for some that’s .bash_profile and for others it might be .bashrc, depending on your nix flavor) and you can stop all of that. I haven’t tried this with other shells aside from bash, but I don’t see why it wouldn’t work.

Basically, this function uses the locate command to find whatever you are looking for just like you do, only it uses a bit of scriptology to filter it down to the exact match of what you are looking for. Yep, that’s right, the exact match! This little tidbit can really help out when you are looking for something, take a look:

## BASH locate function for exact match
## Thanks Dark_Helmet : http://solarum.com/v.php?l=1149LV99
function flocate
{
  if [ $# -gt 1 ] ; then
    display_divider=1
  else
    display_divider=0
  fi

  current_argument=0
  total_arguments=$#
  while [ ${current_argument} -lt ${total_arguments} ] ; do
    current_file=$1
    if [ "${display_divider}" = "1" ] ; then
      echo "----------------------------------------"
      echo "Matches for ${current_file}"
      echo "----------------------------------------"
    fi

    filename_re="^\(.*/\)*$( echo ${current_file} | sed s%\\.%\\\\.%g )$"
    locate -r "${filename_re}"
    shift
    (( current_argument = current_argument + 1 ))
  done
}

It’s just that easy! Copy and paste this into your profile and add a cool helper addon companion function thingy 🙂 I wish I could say I came up with this myself, but I didn’t, I found it in some forums posted by someone named Dark_Helmet (just like the attribution link in the script). I don’t know who you are Mr. Helmet, but I thank you for your sharing this with us all, and I am passing it on! Enjoy!

PERL Trim Functions

PERL is a wonderful scripting language, it is extremely powerful, flexible and portable. It also lacks a couple basic functions that other languages have built in. Fear not my friend, just like the PERL round function, I have functions for other things as well!

One thing I miss is a trim function. They have chop and chomp, but that doesn’t always fit what I want. Below I have included a few suns that will get the job done nicely, check it out. Continue reading PERL Trim Functions

PERL Round Function

Hey all your PERL junkies like me, I have a present for you. Anyone that has done any coding at all other PERL will know (and miss) the round function that most other languages have built in. For those that may not know, the round function lets you do just that, round a number to the specified digit. So, instead of having to use 3.14159265 as an answer for a particular equation, you could round it to 3.14. Nice, huh?

Well, here is a neato little round function that you can drop into your PERL scripts and call to actually round numbers instead of cutting them off with ceil or cut. Check it out:

sub round {
  my($number) = shift;
  return int($number + .5 * ($number <=> 0));
}

There you go!

**Update**
Thanks to Thierry H. for adding a little mod to the round function allowing you to specify the number of decimals to print. Here is the modified function:

sub round {
  my $number = shift || 0;
  my $dec = 10 ** (shift || 0);
  return int( $dec * $number + .5 * ($number <=> 0)) / $dec;
}

You would call it by giving not only the number to round, but how many numbers to show on the right side of the decimal. It will look like so:

$result = round(123.4567,3);

This should return 123.457 (the 6 in the third slot gets rounded to 7). There ya go, thanks for the mod Thierry! You can check out Thierry’s site here.